Workers drilling the first tunnel at the nation's nuclear waste repository in the Nevada desert were exposed to dangerous levels of silica and other cancer-causing dusts in the 1990s, an Energy Department official acknowledged Monday.
Dust masks and respirators were not mandatory, and not all Yucca Mountain project workers used them, said Gene Runkle, the senior Yucca Mountain safety adviser for the federal Office of Civilian Radioactive Waste Management.
Sen. Harry Reid, D-Nev., collected testimony Monday in Las Vegas from Runkle, two former tunnel workers in ill health, two industrial hygienists and a physician.
The senator, the son of a miner who died of lung disease, then accused the federal agency of sacrificing workers' health in its haste to dig the first 5-mile tunnel at Yucca Mountain.
"DOE ignored the threat," Reid said after cutting off comments from Runkle and concluding the Las Vegas field hearing of the Senate Appropriations Committee's subcommittee on Energy and Water. "What has taken place here is just absolutely wrong."
Runkle later defended project administrators' and engineers' efforts to "balance operations and the safety requirements at the time."
"There were safety processes in place and they were taken into account," he said, adding that safety standards became stricter over time.
Runkle heads a silicosis and lung disease screening program that the Energy Department created in January for current and former tunnel workers. He appeared Monday on behalf of Margaret Chu, chief of the Office of Civilian Radioactive Waste Management and the Bush administration's top Yucca Mountain official.
A mandatory respirator protection program began in March 1996, the same year work was stopped for two weeks - from Aug. 20 to Sept. 13 - due to high dust levels at the site, Runkle said.
"We have recognized that we exceeded some of the regulatory limits in the 1990s," Runkle said.
The focus Monday was mostly on silica, a mineral that exists naturally in desert soils and in the rocks at Yucca Mountain, 90 miles northwest of Las Vegas.
Long-term exposure to inhaled silica has long been known to cause silicosis, a chronic and progressive lung disease with symptoms including coughing and shortness of breath.
Gene Griego, 52, a former tunnel worker now being treated for silicosis, and Jeffrey Dean, a former Yucca Mountain miner diagnosed with a similar disease, said workers also faced a threat from exposure to airborne specks of carcinogenic erionite and mordenite.
Reid and other Nevada officials are fighting the Energy Department's plan to store 77,000 tons of the nation's nuclear waste at the repository beginning in 2010.